In a normal atmospheric environment, the storage life of perishable food products is limited. Traditional modified atmosphere packaging replaces the normal atmospheric environment before storage or shipment, but the environment is not modified over time. The traditional modified atmosphere packaging has limitations stemming from no atmosphere modification after sealing until delivery. This can result in premature product spoilage caused by unacceptably high oxygen concentrations due to emissions from the product or interior packaging components, the permeability of the packaging materials or a broken seal. Some prior art modified atmosphere shipping containers rely on gas permeable membranes to regulate the gas composition within a container by molecular separation. Other prior art containers rely on a reactive fuel cell using a chemical process to remove oxygen. The limitations of the current modified atmosphere shipping systems include their high cost, operational complexity, the inability to optimize the ratio of inert gasses, and the limited rate of gas treatment or discharge. These limitations are addressed by the inventions described herein.